Cyclin G1 (CCNG1)

Cyclin G1 is a protein that plays a role in growth regulation and is associated with cell cycle control, particularly at the G2/M phase checkpoint. It can induce cell cycle arrest at this stage in response to DNA damage. Transcriptional activation of CCNG1 can be induced by tumor suppressor p53, suggesting it acts as an intermediate through which p53 mediates its effects on cell cycle arrest and DNA repair pathways. It has also been implicated in spatial coupling between autophagy compartments and mTOR signaling during cellular stress responses. Altered expression or regulation of Cyclin G1 has been linked to cancer development, making it a potential biomarker for cancer prognosis and therapy selection.

Dominant-negative forms of Cyclin G1 have shown anticancer activity by triggering programmed cell death (apoptosis). MicroRNAs such as miR-516b act as tumor suppressors by directly targeting CCNG1 expression.